MvP GRF v2

[Tsudere]

Hi everybody.

Actually I'm working on Mobsprites for my own grf. I wanted to implant Bakonava for all MvPs, but my client get a time out when Bakonava is on the screen. I wonder whats wrong, because I don't get an error and it's running for a few seconds before my client don't give any response.
I guess it's not enough to overwrite a monster with .act and .spr files. There must be something missing, but I never played seen Bakonava on usal enviroment on renewal servers.
And probably I want this sprite running on pre-renewal.

Any suggestions what is missing?